It might be time for larger pots or to think about getting your Holly Trees in the ground.

Holly is not an easy plant to establish. It needs to be planted in sun or partial shade. Plenty fo peat moss or compost should have been added to the planting hole. Try pruning back some of the branches. The soil needs to be well-drained and steps should be taken to improve the soil drainage if it is not draining well. Holly also like acidic soil.